LEMON Manuals: Even more car manuals for everyone
Home >> Toyota >> 2017 >> 4Runner TRD Pro >> Repair and Diagnosis >> Brakes >> Anti-Lock Brakes >> Vehicle Stability Control System (For Hydraulic Brake Booster) - Diagnostic Codes (43, C0226-C1422) >> VEHICLE STABILITY CONTROL SYSTEM (for Hydraulic Brake Booster) >> DTC C1380: Stop Light Control Relay Malfunction [08/2015 - 08/2019] >> Procedure

DTC C1380: Stop Light Control Relay Malfunction [08/2015 - 08/2019]: Procedure

  1. CHECK STOP LIGHT OPERATION 
    1. Check that the stop lights come on when the brake pedal is depressed and go off when the brake pedal is released.

      OK

      Condition Illumination Condition
      Brake pedal depressed. ON
      Brake pedal released. OFF

    Result: 

    NG 

    INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2019] )

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (STOP LIGHT SW) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Select the Data List on the Techstream (Refer to DATA LIST / ACTIVE TEST [08/2015 - 08/2019] ).
      ABS/VSC/TRAC

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light SW Stop light switch assembly / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released      		 -
    4. Check that the stop light switch assembly condition observed on the Techstream changes according to brake pedal operation.

      OK

      The Techstream displays ON or OFF according to brake pedal operation.

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  3

  3. PERFORM ACTIVE TEST USING TECHSTREAM (STOP LIGHT RELAY) 
    1. Select the Active Test on the Techstream (Refer to DATA LIST / ACTIVE TEST [08/2015 - 08/2019] ).
      ABS/VSC/TRAC

      Tester Display Test Part Control Range Diagnostic Note
      Stop Light Relay Stop light control relay (Stop light switch assembly) Relay (Switch) ON/OFF Stop lights come on
    2. Perform the Active Test of the stop light control relay (stop light switch assembly) using the Techstream.
    3. Select the Data List on the Techstream (Refer to DATA LIST / ACTIVE TEST [08/2015 - 08/2019] ).
      ABS/VSC/TRAC

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light Relay Output Stop light control relay (Stop light switch assembly) output / ON or OFF ON: Relay output on
      OFF: Relay output off      		 -
    4. Check for stop light control relay (stop light switch assembly) operation using the Data List and stop light operation by performing an Active Test.

      Result

      Result Proceed to
      Data List content and stop light operation are normal. A
      Data List content and stop light operation are abnormal or Data List content is normal but stop lights do not turn on or off. B

    Result: 

    B 

    See step  6

    Result: 

    A 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (STP2 TERMINAL) 
    1. Turn the ignition switch off.
      GTY707116Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    3. Disconnect the A6 skid Control ECU connector.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A6-45 (STP2) - Body ground Stop light switch assembly ON (Brake pedal depressed) 11 to 14 V
      A6-45 (STP2) - Body ground Stop light switch assembly OFF (Brake pedal released) Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU)

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP2 CIRCUIT) 

    Result: 

    OK 

    See step  5

  5. RECONFIRM DTC 
    1. Reconnect the skid control ECU connector.
    2. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
    3. Turn the ignition switch to ON.
    4. Perform a road test.
    5. Check if the same DTC is output (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).

      Result

      Result Proceed to
      DTC C1380 is not output. A
      DTC C1380 is output. B

    Result: 

    A 

    CHECK FOR INTERMITTENT PROBLEMS 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2019] )

    Result: 

    B 

    REPLACE MASTER CYLINDER SOLENOID 

    (Refer to DISASSEMBLY [08/2015 - ] )

  6. CHECK STOP LIGHT SWITCH ASSEMBLY 
    1. Check the stop light control relay (stop light switch assembly) (Refer to ON-VEHICLE INSPECTION [08/2015 - 08/2019] ).

      OK

      The stop light control relay (stop light switch assembly) is normal.

    Result: 

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY 

    (Refer to REMOVAL [08/2015 - ] )

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (STPO TERMINAL) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
      GTY711923Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the A6 skid control ECU connector.
    3. Turn the ignition switch to ON.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A6-16 (STPO) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU)

    Result: 

    OK 

    REPLACE MASTER CYLINDER SOLENOID 

    (Refer to DISASSEMBLY [08/2015 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STPO CIRCUIT) 

  8. CHECK HARNESS AND CONNECTOR (STP TERMINAL) 
    1. Turn the ignition switch off.
      GTY702246Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    3. Disconnect the skid control ECU connector.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A6-7 (STP) - Body ground Stop light switch assembly ON (Brake pedal depressed) 11 to 14 V
      A6-7 (STP) - Body ground Stop light switch assembly OFF (Brake pedal released) Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU)

    Result: 

    OK 

    REPLACE MASTER CYLINDER SOLENOID 

    (Refer to DISASSEMBLY [08/2015 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 

scientia non olet · About LEMON Manuals